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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___ALGORITHM_EQUAL_RANGE_H10#define _LIBCPP___ALGORITHM_EQUAL_RANGE_H11 12#include <__algorithm/comp.h>13#include <__algorithm/comp_ref_type.h>14#include <__algorithm/half_positive.h>15#include <__algorithm/iterator_operations.h>16#include <__algorithm/lower_bound.h>17#include <__algorithm/upper_bound.h>18#include <__config>19#include <__functional/identity.h>20#include <__type_traits/invoke.h>21#include <__type_traits/is_callable.h>22#include <__type_traits/is_constructible.h>23#include <__utility/move.h>24#include <__utility/pair.h>25 26#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)27# pragma GCC system_header28#endif29 30_LIBCPP_PUSH_MACROS31#include <__undef_macros>32 33_LIBCPP_BEGIN_NAMESPACE_STD34 35template <class _AlgPolicy, class _Compare, class _Iter, class _Sent, class _Tp, class _Proj>36_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_Iter, _Iter>37__equal_range(_Iter __first, _Sent __last, const _Tp& __value, _Compare&& __comp, _Proj&& __proj) {38 auto __len = _IterOps<_AlgPolicy>::distance(__first, __last);39 _Iter __end = _IterOps<_AlgPolicy>::next(__first, __last);40 while (__len != 0) {41 auto __half_len = std::__half_positive(__len);42 _Iter __mid = _IterOps<_AlgPolicy>::next(__first, __half_len);43 if (std::__invoke(__comp, std::__invoke(__proj, *__mid), __value)) {44 __first = ++__mid;45 __len -= __half_len + 1;46 } else if (std::__invoke(__comp, __value, std::__invoke(__proj, *__mid))) {47 __end = __mid;48 __len = __half_len;49 } else {50 _Iter __mp1 = __mid;51 return pair<_Iter, _Iter>(std::__lower_bound<_AlgPolicy>(__first, __mid, __value, __comp, __proj),52 std::__upper_bound<_AlgPolicy>(++__mp1, __end, __value, __comp, __proj));53 }54 }55 return pair<_Iter, _Iter>(__first, __first);56}57 58template <class _ForwardIterator, class _Tp, class _Compare>59[[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator, _ForwardIterator>60equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp) {61 static_assert(__is_callable<_Compare&, decltype(*__first), const _Tp&>::value, "The comparator has to be callable");62 static_assert(is_copy_constructible<_ForwardIterator>::value, "Iterator has to be copy constructible");63 return std::__equal_range<_ClassicAlgPolicy>(64 std::move(__first),65 std::move(__last),66 __value,67 static_cast<__comp_ref_type<_Compare> >(__comp),68 std::__identity());69}70 71template <class _ForwardIterator, class _Tp>72[[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator, _ForwardIterator>73equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {74 return std::equal_range(std::move(__first), std::move(__last), __value, __less<>());75}76 77_LIBCPP_END_NAMESPACE_STD78 79_LIBCPP_POP_MACROS80 81#endif // _LIBCPP___ALGORITHM_EQUAL_RANGE_H82